Evolving trends in the management of acute appendicitis during COVID-19 waves. The ACIE appy II study

Background: In 2020, ACIE Appy study showed that COVID-19 pandemic heavily affected the management of patients with acute appendicitis (AA) worldwide, with an increased rate of non-operative management (NOM) strategies and a trend toward open surgery due to concern of virus transmission by laparoscopy and controversial recommendations on this issue. The aim of this study was to survey again the same group of surgeons to assess if any difference in management attitudes of AA had occurred in the later stages of the outbreak. Methods: From August 15 to September 30, 2021, an online questionnaire was sent to all 709 participants of the ACIE Appy study. The questionnaire included questions on personal protective equipment (PPE), local policies and screening for SARS-CoV-2 infection, NOM, surgical approach and disease presentations in 2021. The results were compared with the results from the previous study. Results: A total of 476 answers were collected (response rate 67.1%). Screening policies were significatively improved with most patients screened regardless of symptoms (89.5% vs. 37.4%) with PCR and antigenic test as the preferred test (74.1% vs. 26.3%). More patients tested positive before surgery and commercial systems were the preferred ones to filter smoke plumes during laparoscopy. Laparoscopic appendicectomy was the first option in the treatment of AA, with a declined use of NOM. Conclusion: Management of AA has improved in the last waves of pandemic. Increased evidence regarding SARS-COV-2 infection along with a timely healthcare systems response has been translated into tailored attitudes and a better care for patients with AA worldwide

Global disparities in surgeons’ workloads, academic engagement and rest periods: the on-calL shIft fOr geNEral SurgeonS (LIONESS) study

: The workload of general surgeons is multifaceted, encompassing not only surgical procedures but also a myriad of other responsibilities. From April to May 2023, we conducted a CHERRIES-compliant internet-based survey analyzing clinical practice, academic engagement, and post-on-call rest. The questionnaire featured six sections with 35 questions. Statistical analysis used Chi-square tests, ANOVA, and logistic regression (SPSS® v. 28). The survey received a total of 1.046 responses (65.4%). Over 78.0% of responders came from Europe, 65.1% came from a general surgery unit; 92.8% of European and 87.5% of North American respondents were involved in research, compared to 71.7% in Africa. Europe led in publishing research studies (6.6 ± 8.6 yearly). Teaching involvement was high in North America (100%) and Africa (91.7%). Surgeons reported an average of 6.7 ± 4.9 on-call shifts per month, with European and North American surgeons experiencing 6.5 ± 4.9 and 7.8 ± 4.1 on-calls monthly, respectively. African surgeons had the highest on-call frequency (8.7 ± 6.1). Post-on-call, only 35.1% of respondents received a day off. Europeans were most likely (40%) to have a day off, while African surgeons were least likely (6.7%). On the adjusted multivariable analysis HDI (Human Development Index) (aOR 1.993) hospital capacity > 400 beds (aOR 2.423), working in a specialty surgery unit (aOR 2.087), and making the on-call in-house (aOR 5.446), significantly predicted the likelihood of having a day off after an on-call shift. Our study revealed critical insights into the disparities in workload, access to research, and professional opportunities for surgeons across different continents, underscored by the HDI

Bending and stamping processes of FSWed thin sheets in aluminium alloy

none3noThe present investigation aims at studying post-welding forming operations of friction stir welded AA1050 aluminium thin sheets. A preliminary investigation has allowed to define the rotational and welding speed values leading to friction stir welded joints with high mechanical properties. Then, formability and elastic springback were evaluated using the hemispherical punch and bending tests, respectively. A microstructural investigation has allowed to relate the mechanical properties of joints to microstructure. Finally, the friction stir welded assemblies were subjected to air bending and stamping experiments in order to evaluate their attitude to undergo to sheet metal forming operations.Simoncini, Michela; Panaccio, Lorenzo; Forcellese, ArchimedeSimoncini, Michela; Panaccio, Lorenzo; Forcellese, Archimed

Design of Stamping Processes of Pinless FSWed Thin Sheets in AA1050 Alloy for Motomotive Applications Using FEM

In the present paper, the cold stamping of friction stir welded AA1050-O thin sheets, obtained using a pinless tool, was studied. A preliminary investigation allowed to define the weldability window, in terms of the rotational and welding speed values, leading to joints with the desired mechanical properties. Then, the constitutive behavior of both the parent material and welded zone was characterized by means of uniaxial tensile tests. The constitutive equations obtained by analyzing the experimental results were implemented into the FEM code used to simulate the cold stamping process of FSWed blanks. The virtual prototypes were validated by performing stamping experiments of the FSWed blanks and comparing the predicted and measured results in terms of sheet thickness, and major strain vs. minor strain data

Design of Stamping Processes of Pinless FSWed Thin Sheets in AA1050 Alloy for Motomotive Applications Using FEM

In the present paper, the cold stamping of friction stir welded AA1050-O thin sheets, obtained using a pinless tool, was studied. A preliminary investigation allowed to define the weldability window, in terms of the rotational and welding speed values, leading to joints with the desired mechanical properties. Then, the constitutive behavior of both the parent material and welded zone was characterized by means of uniaxial tensile tests. The constitutive equations obtained by analyzing the experimental results were implemented into the FEM code used to simulate the cold stamping process of FSWed blanks. The virtual prototypes were validated by performing stamping experiments of the FSWed blanks and comparing the predicted and measured results in terms of sheet thickness, and major strain vs. minor strain data

Stamping of FSWed AA1050 aluminium thin sheets for motomotive components

The present investigation aims at studying the cold stamping of friction stir welded AA1050 aluminium thin sheets (1.5 mm in thickness), for motomotive applications. A preliminary investigation has allowed to define the rotational and welding speed values leading to friction stir welded joints with high mechanical properties, in terms of ductility and flow stress. Then, formability of the welded joints, in terms of forming limit curves at the onset of necking, was evaluated using the hemispherical punch test. The effect of the welding line orientation on formability was also taken into account. A microstructural investigation has allowed to relate the mechanical properties of joints to microstructure. Finally, the validity of such investigations was proven by performing cold stamping experiments on friction stir welded blanks up to the obtaining of the desired geometry

Investigation on process parameters affecting blanking of AISI 1006 low carbon steel

A blanking apparatus was designed and built in order to study the effects of the process parameters on blanking low carbon steel disks, with particular reference to the study of punch-die gap influence and Brozzo's damage criterion by keeping punch and die fillet radii constant. The goal of the shearing tests was to optimize the gap between punch and die, according to the material damage and the force curves obtained by experimental tests. By using a 2D axis-symmetry FE model, the authors studied a set of parameters in order to reduce damage. After studying the material damage by a first simulation series, a second series was carried out in order to evaluate the punch-die gap effects on force-stroke trend; good results in term of external surface finish were obtained in the geometry of the final workpiec

Investigation on friction conditions during a severe bending deformation on a thick plate

In this paper, the friction behaviour in a severe bending process of a thick plate was investigated, taking into account both dry and lubricated conditions. Early experimental tests were performed to obtain mechanical properties of the low carbon steel AISI 1006, to be used as input in FE solver. Besides a 3D thermo-mechanical model based on FEM was developed to predict stress and strain distributions and final component dimensions. The second experimental series was composed of a coining process and a forming operation to reach the size of the final part. The analysis and the control of the friction conditions has permitted to obtain a product of higher quality that permitted to avoid all the secondary machining operations previously require

Minimally Invasive Treatment of Sporadic Burkitt’s Lymphoma Causing Ileocaecal Invagination

Introduction. Primary NHL (non-Hodgkin lymphoma) of the colon represents only 0.2% to 1.2% of all colonic malignancies. Burkitt’s lymphoma (BL) is usually a disease reported in children and young people, most of them associated with EBV or HIV infection. We describe a rare case of intestinal obstruction due to sporadic Burkitt’s lymphoma causing ileocaecal invagination explaining our experience Methods. A 31-year-old man presented with diffuse colic pain and weight loss. Clinical examination revealed an abdominal distension with pain in the right iliac fossa. Colonoscopy documented a caecal large lesion with ulcerated mucosa. Computed tomography (CT) have shown a 60 × 50 mm right colic parietal lesion with signs of ileocolic intussusception. Results. Laparoscopic right hemicolectomy was performed. Postoperative period was uneventful. CD20+ high-grade B-cell Burkitt’s lymphoma was confirmed by immunohistochemistry (CD20+, CD79+, and CD10+) and FISH test (t (8;14) (q24; q32). The patient was subsequently treated with adjuvant combination chemotherapy (Hyper-CVAD) and is alive and disease-free at 8 months follow-up. Discussion. Adult sporadic Burkitt’s lymphoma (BL) causing intestinal obstruction due to ileocaecal intussusception is an extremely rare occurrence and a diagnostic dilemma. Despite the surgical approach is selected based on patient’s conditions and surgeon’s expertise, minimally invasive method could be preferred

Design of Stamping Processes of Pinless FSWed Thin Sheets in AA1050 Alloy for Motomotive Applications Using FEM

In the present paper, the cold stamping of friction stir welded AA1050-O thin sheets, obtained using a pinless tool, was studied. A preliminary investigation allowed to define the weldability window, in terms of the rotational and welding speed values, leading to joints with the desired mechanical properties. Then, the constitutive behavior of both the parent material and welded zone was characterized by means of uniaxial tensile tests. The constitutive equations obtained by analyzing the experimental results were implemented into the FEM code used to simulate the cold stamping process of FSWed blanks. The virtual prototypes were validated by performing stamping experiments of the FSWed blanks and comparing the predicted and measured results in terms of sheet thickness, and major strain vs. minor strain data